Add logging capabilities to class Compiler

[ghost]

( use a simple and widely accepted logging framework; for KISS, we could use java.util.logging.* )

For sure, most compilers don't log anything. When compiling critical stuff in industry, however, you'd want at least to be able to set a verbosity level e.g. ALL, DEBUG, MAJOR, CRITICAL, NONE. Would be nice to combine that with logging behaviour.

[nobeh]

Hi Jan,

Thanks for your suggestion. However, please just note that we provide integration of jabsc mainly through Maven. And, in there, we take advantage of logging through what Maven provides.